INTENSITE SEGKEGATION. 337 



their confinement. This is a method o£ improving the race that 

 might be carried further than it has been. In some countries 

 the insane are confined in asylums and not allowed to marry ; 

 and in other countries ecclesiastical and military restrictions 

 prevent certain portions of the commuuitj^ from raising families. 



Eesult of the foregoing t^urveij of Selectional Intension. 



The analysis which we have now completed enables us to see 

 how far changes in the form of Selection are due to changes in 

 the environment, and how far to changes in the organism. We 

 find : — Eirst, that all the forms of Eeflexive Selection are due to 

 the relations of members of the same species to each other, and 

 are liable to change without any change in the environments. 

 Second, that Active Natural Selection is due to change in the 

 successful use of the powers of the organism in dealing with the 

 environment, and is not dependent on change in the environ- 

 ment. Third, that Passive Natural Selection, which is due to the 

 exposure of the organism to a different environment, is often 

 produced by the organism's entering a new environment without 

 there being any change in either the new or the old environment. 

 Fourth, that when Passive Natural Selection is produced by 

 change in the environment, the more efiective forms of Selection 

 do not appear till the organism has so multiplied as to produce 

 what I call Superlative Natural Selection through intense com- 

 petition between rival individuals of the same species in gaining 

 possession of limited resources. And, fifth, that Passive Compa- 

 rative Natural Selection, which depends on change in the envi- 

 ronment, without special rivalry between the members of one 

 species, also depends on variation in the adaj)tations of the 

 organism, many of which variations do not depend on that change 

 in the environment which has produced the change in the Natural 

 Selection, nor, indeed, on any change in the environment excejjt 

 those fundamental physical changes by which the world has 

 passed from its primitive gaseous to its present partially liquid 

 and solid state, rendering it a fit abode for organisms. 



Eliminational Intension. 



Eliminational Intension is Segregation and divergence pro- 

 duced by tlie indiscriminate destruction or failure to propagate 

 of part of the individuals of similar sections of a species. Though 



